On Tue, Mar 15, 2011 at 6:00 PM, Jed Brown <jed at 59a2.org> wrote: > On Tue, Mar 15, 2011 at 23:50, Matthew Knepley <knepley at gmail.com> wrote: > >> That is not what I have here. I want to change a portion, but outside of >> that I want it to fall back to a global matrix. > > > You were going to put your MatShell in the "pmat" slot, right? What are you > going to use for preconditioning the other blocks? If it's the same as in > "mat", you could use a MatNest for both operators and put the special sauce > in that slot of the "pmat". >
This is the same objection Barry has. I do not want this tied to a particular matrix impl for the global matrix. > If you assemble the matrix entirely monolithically (using MatSetValues > globally instead of MatSetValuesLocal on each physics separately), then we > haven't written MatSetValues_Nest yet so maybe your MatShell is the right > idea. > > > Related: What do people think about having MatGetSubMatrix() retain > ownership of the submatrix? > Does it matter with our interface? Should be transparent. Matt -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20110315/f77389fc/attachment.html>
